Kim Hammond does not want responsibility for her neighbours’ livelihoods, or for the crops which stretch in all directions as far as the eye can see, or for the earth itself in this corner of California.

But these days, her little bungalow office in the yard of her family’s drilling company can feel like Mount Olympus.

“It’s just way too stressful, playing God,” said Hammond, a grandmother who co-owns the company and works as its secretary. “Every day we have people on the phone or here in person, pleading. It breaks your heart. But I always give it to them straight. I don’t sugarcoat it.”

It is her job to tell farmers when – or if – a team can visit their property to drill for groundwater and make a well which can save a crop, avert bankruptcy and, perhaps, preserve a way of life.

As California faces a likely fourth year of drought, demand for drilling in the Central Valley has exploded. Hammond’s company, Arthur & Orum, can barely keep up: its seven rigs are working flat-out, yet a white folder with pending requests is thicker than three telephone books.

The waiting list has grown to three years, leaving many farmers to contemplate parched fields and ruin in what has been one of the world’s most productive agricultural regions. It supplies half of America’s fruit, nuts and vegetables.

“We’re overwhelmed. We’re going crazy,” said Hammond. “Everyone is in a desperate situation. Everyone has a sad story.”

Arthur & Orum has bought an additional rig for $1.2m, and out-of-state drillers have moved into the area. But as drills criss-cross the landscape, boring ever deeper into the earth, there is a haunting fear: what if they suck up all the groundwater? What if, one day, the water runs out?

“We’re having to go deeper and deeper,” said Hammond. “They say we’re tapping water millions of years old. That boggles the mind. I can hardly grasp it.”

Meagre rain has depressed the water table so much that in some areas drills bore more than 1,500ft. Sucking up water stored long underground can cause soil to subside and collapse. In some places the land has dropped by a foot. Hydrogeologists have warned that pumping out groundwater faster than it can recharge threatens springs, streams and ecosystems.

Hammond said she was conflicted that the family business was saving some neighbours’ livelihoods for now but risked long-term devastation. “They say we’re cutting our own throats. I live here. I don’t want to live in the desert.”

Sensing drama, a reality TV production company has asked the family company about doing a show.

Desperate times

The spectre of desertification inched closer this week. The Sierra Nevada snowpack, which supplies about a third of California’s water, is paltry. The California Cooperative Snow Surveys Program found just 6.7in of snow – close to the lowest on record – at a survey spot near Echo Summit.

Storms in December and February mean reservoirs hold more water than this time last year, but they remain well below average. Conservation efforts are slipping. In January urban areas used 9% less water than January 2013, far below the official target of 20%.

El Niño, the weather system which often douses the western US, has returned after a five-year absence but promises little relief. Mike Halpert, deputy director of the Climate Prediction Center, said in a statement it is “likely too late and too weak to provide much relief for drought-stricken California”.

Federal officials warned last week that for a second consecutive year irrigation projects were likely to allocate zero water to Central Valley farmers without senior water rights.

“This is an absolutely devastating shock,” said Ryan Jacobsen, executive director for the Fresno County farm bureau. “Unless things change dramatically in the next six weeks, we expect 2015 to be much worse than last year.”

Crisis is apparent as you drive through the valley. Many fields are fallow – some idled last year, others more recently. The earth is baked hard. Preliminary estimates suggest Fresno may have recorded its warmest-ever February, prolonging what has been dubbed the “time without winter”. Roadside signs warn of the consequences. “No water = no food.” “Food grows where water flows.”

The American Meteorological Society has found no definitive link between climate change and California’s drought, but a recent report in the Proceedings of the National Academy of Sciences said rising temperatures caused dry periods to overlap more often with warm periods.

‘It’s like frigging chemotherapy’

Computers and state-of-the-art irrigation have not spared Shawn Coburn, 46, who owns a farm near Dos Palos, in Merced County. Last year he abandoned alfalfa and pomegranates and cut his 1,000-acre tomato crop by two-thirds. “This year I’ll fallow all of it. You’ll see a lot more land fallowed this year.”

Like many farmers, he assailed pumping restrictions aimed at protecting the delta smelt, a threatened fish, and other environmental regulations, branding them ruinous and futile. Environmentalists call them vital to the entire ecosystem.

Coburn has spent almost $4m on wells but said in some areas water plumbed from ever lower depths was often laden with salt and other minerals. “It’s like frigging chemotherapy,” he said. “You can get away with it for one year. By the third year you’re basically killing the tree.”

Clarence Freitas, 56, who owns 70 acres of almonds and grapes, watched with relief as a team from Arthur & Orum drilled into his baked soil, boring through 80ft a day until reaching 440ft and an expensive, urgent replacement for his old 160ft-deep well.

“My heart hurts, my bank account hurts,” he said, as muddy water gushed from pipes. Neighbours advised him to go deeper, in anticipation of the water table plunging further, but Freitas said the men in his family tended to die young – “I hope it’ll last 20 years and by then I’ll be gone.” He was not optimistic about the valley. “This could go back to being desert, the way it was before irrigation.”

Many farmers are descendants of migrants who fled here to escape the 1930s dust bowl, a trauma immortalised in John Steinbeck’s novel The Grapes of Wrath. It could happen again, except this time in California’s man-made Eden, said Matt Hammond, 51, Kim’s husband, on his way to a drilling site.

“They’ll keep growing crops around here until they pump the valley dry. If something doesn’t change, everything will dry up and die. It won’t be farmable anymore.”

The community had hoped for a “miracle March” of bountiful rain but that seems unlikely, he said, scanning azure skies. “Nobody’s fault but God’s.”